Albert Barnes on John 13:3

Jesus knowing, &c. With the full understanding of his dignity and elevation of character, he yet condescended to wash their feet. The evangelist introduces his washing their feet by saying that he was fully conscious of his elevation above them, as being intrusted with all things, and this made his humiliation the more striking and remarkable. Had he been a mere human teacher or a prophet, it would have been remarkable; but when we remember the dignity of his nature, it shows how low he would stoop to teach and save his people.

Had given all things, &c. Mt 28:18.

Was come from God. Jn 8:42.

Went to God. Was about to return to heaven. See Jn 6:61,62.

(e) "knowing that the Father" Mt 28:18, He 2:8 (f) "he was come from God" Jn 17:11